A thick concrete wall can keep your house cool. Steel will make your house hot unless you insulated the walls well. Insulated walls don't work very well in a flood zone. When they get wet, you need to tear them apart. You will need concrete for the foundation most likely unless you are driving steel pylons. There is probably a combination of the two that will suit your needs best. It would be helpful to know what you want to achieve by using steel. There are advantages to both. Steel floors can be cantilevered further. It is easier to make bigger window openings. Floor and roof spans can be lighter and quicker to build with steel, but the roof will get hotter and therefore need good insulation and need to be well ventilated. These are just general assumptions of certain building practices so that you know what to ask people where you live. The practices and resources vary from place to place and building something for a specific purpose can change the benefits of one material or the other. My best guess is that you will probably want to use both.

Poor insulation = poor temperature control. Ventilation might help (in the summer) but won't do anything in winter. Your poor insulation is the GREATEST problem. Old windows is the next issue. The way to solve this = NEW insulation for exterior walls AND under the roof. Good luck. It is an expensive fix.

Depends on what needs the sound proofing. I can't explain Acoustic Drywall if you want to insulate the floor. I can't talk about floor underlay if you want to insulate a wall or a ceiling. What you are trying to achieve (one room or an entire home) and what your expectations are will also decide "best" way to add acoustic insulation. The "Best" way to do it is to BUILD IT properly (with the acoustic materials used from the start) with acoustic materials. The "worst" way to do it is to retrofit the acoustic insulation at a later date.

I need a solution for penthouse roof that is constructed in the 3rd floor.. The building is in the countryside wherein all the 4 sides is clear without any buildings. Concrete slab is heavy, since the footing may not be conducive to take the load, looking for a light weight roofing solution, whereby the roof offers concrete like or better insulation from rain sound and other sounds, insulated from heat yet economical and can bear the wind thrust on the 3rd floor.